There may be a positive connection between caffeine consumption and breast cancer. Depending on menopausal status, enjoying that morning cup of coffee may actually decrease the risk of cancer in some women.
This article will discuss the relationship between caffeine and breast cancer and how drinking coffee and tea may benefit women, even improving survival after a breast cancer diagnosis and treatment.
Caffeine consumption has been associated with a decreased risk of breast cancer in a few studies, though the results have been inconsistent. Furthermore, more research is needed into the reason for the possible link, as well as the ideal timing and amount of caffeine that could potentially have any effect on breast cancer.
One group of researchers in Italy examined 21 studies on this subject but were unable to find a relationship between caffeine consumption and the risk of breast cancer. However, when they looked at a small subset of the data, they discovered that drinking four cups of coffee per day was associated with a 10% reduction in postmenopausal cancer risk.
A Swedish study echoed this sentiment, noting that coffee consumption could decrease breast cancer risk among postmenopausal women. In this study, women who consumed three to four cups of coffee per day had a slightly lower rate of breast cancer than women who consumed two cups of coffee per day or less. And women who consumed five or more cups of coffee per day had an even lower rate of breast cancer.
Researchers who conducted a large multinational trial also suggested that a higher intake of caffeinated coffee is associated with a lower risk of breast cancer in postmenopausal women.
Although the above research in support of caffeine for reduced breast cancer risk is notable, the relationship between caffeine and breast cancer is complicated and unclear. Conflicting conclusions only support how much more there is to know about this topic.
The Swedish study that showed a reduction in breast cancer in postmenopausal women who consumed coffee also found that caffeinated tea consumption was associated with an increase in breast cancer, though the reason for this is unclear.
And, the multinational trial, which also looked at tea and coffee consumption, did not prove any relationship between tea (or decaffeinated coffee) and premenopausal or postmenopausal breast cancer.
While research is ongoing, it's important to remember that many foods and beverages have components that may, together or alone, have an influence on cancer risk.
Furthermore, a different multicenter trial (involving more than one research institution) showed that the potentially beneficial effect of coffee on breast cancer must be weighed carefully when it comes to postmenopausal women using hormone therapy.
Researchers found that postmenopausal women who consumed more than four cups of coffee per day had a 16% reduced risk of breast cancer compared to women who consumed less than seven cups of coffee per week. However, women who used postmenopausal hormone therapy and consumed more than four cups of coffee per day had a 22% greater risk of breast cancer than women consuming less than seven cups per week.
Not only do results on the effect of coffee on breast cancer risk vary with age, menopausal status, and more, but the method by which it's prepared adds another variable. A 2019 study on Chinese women in Hong Kong found that consuming coffee products did not increase the risk of breast cancer.
When broken down by preparation methods, however, there were significant differences. Women who drank brewed coffee, for instance, were, on average, 52% less likely to develop breast cancer. In contrast, those who drank instant coffee were 50% more likely to develop the disease.
Just as proper preparation of green tea is essential to obtain the phytonutrients present, the way coffee is prepared could easily affect the nutrients (or carcinogens, cancer-causing agents) present.
There are many factors at play when it comes to the relationship between coffee and breast cancer. Hormone therapy and other risk factors play a far stronger role on the risk of breast cancer than coffee does.
Caffeine has antioxidant and anti-inflammatory functions. Antioxidants counteract oxidation—a chemical process that leads to cancer and heart disease. Inflammation worsens disease, including cancer. For these reasons, caffeine has been considered as a possible treatment for breast cancer when combined with traditional therapies.
A 2020 study showed that that caffeine combined with chemotherapy drug, cisplatin, is an effective treatment for breast cancer by shifting the energy metabolism of two known triple-negative breast cancer lines, and significantly increasing the efficacy of cisplatin to treat the cancerous cells. Triple negative breast cancer is highly aggressive due to the absence of hormone receptors.
A laboratory experiment evaluated the response of cancer cells to caffeine. The researchers found that cell growth was suppressed in estrogen receptor-positive (ER+) and estrogen receptor-negative (ER-) samples.
They also noted that women who consumed high amounts of caffeine and were treated with tamoxifen for breast cancer prevention were less likely to develop the condition. The researchers theorized that caffeine can make women more sensitive to the beneficial effects of the drug.
Because findings in laboratory experiments are not always the same when they are applied to humans, the effects of caffeine on breast cancer cells would have to be replicated in humans in a clinical trial before it would be accepted as a treatment for breast cancer.
A 2021 study suggests coffee may improve breast cancer survival, according to the American Institute for Cancer Research. People drinking more than three cups of coffee a day had a 25% lower risk of dying from breast cancer compared with those who abstained from coffee.
People drinking three cups of tea daily after a breast cancer diagnosis had a 26% lower risk of dying from any cause compared with people who did not drink tea.
Other factors included breast cancer treatment, body mass index (BMI), and physical activity.
Many people who have had breast cancer may worry about the risk of recurrence, especially upon learning that those who have estrogen receptor-positive breast cancer have an increased chance of recurrence after the five-year mark than in the first five years following treatment.
While there is no solid evidence of coffee intake and breast cancer recurrence risk, the caffeinated beverage green tea might be a safer option to consider.
Not only has green tea consumption been associated with a lower risk of developing breast cancer, it's been demonstrated to have anticancer properties, and its most powerful link appears to be in reducing the risk of late recurrence of breast cancer (cancer that returns after five years).
Since the risk of recurrence of estrogen receptor-positive breast cancer remains constant for at least 20 years, this may be good news for those who enjoy green tea.
Can Green Tea Help Prevent or Treat Cancer?The right amount or maximum amount of caffeine differs for everyone, but it can range from one to five servings of a caffeinated beverage or food per day.
For the casual coffee drinker, having a cup can be a nice way to start your day and help you focus. It also may help with headaches, even migraines. However, people with certain health conditions like high blood pressure may want to ease up on the caffeine.
Beyond its potential influence on cancer risk, caffeine may affect breast pain. For instance, some women with fibrocystic breast tissue notice that when they avoid caffeinated products, their breast symptoms improve. This could be related to caffeine's tendency to heighten symptom awareness, which can increase pain sensitivity.
Research is promising, though, on both coffee and green tea consumption and cancer risk, with more studies on the way.
Though more studies are needed, some research has linked caffeine consumption with a decreased risk of breast cancer in some women. However, women with fibrocystic breast tissue may experience less pain and discomfort when they avoid caffeine. Caffeine has a tendency to heighten symptom awareness, which can increase pain sensitivity.
According to the American Institute for Cancer Research, a 2021 study suggests coffee improves breast cancer survival rates. Drinking more than three cups of coffee a day was associated with a 25% lower risk of dying from breast cancer compared with people who abstained from coffee.
Also, women drinking three cups of tea daily after a breast cancer diagnosis have a 26% lower risk of dying from any cause compared with people who did not drink tea.
No, caffeine does not cause breast cysts. However, some women with fibrocystic breast tissue notice that when they avoid caffeinated products, their breast symptoms improve.
Yes, caffeine consumption is linked to estrogen changes. Hormone therapy and other risk factors play a far stronger role on the risk of breast cancer than coffee does, however.